The present invention relates to an assembly for use in examining fecal matter to determine the presence of ova or eggs of parasites which may be present therein. More specifically, the present invention is characterized by novel features of construction and arrangement providing a unit facilitating easier and more sanitary handling of the fecal matter and including a novel mixing or separating means to ensure good sampling of the ova present in the specimen examined.
Apparatus and method for examining fecal matter for the presence of ova are not new per se. For example, the Studer U.S. Pat. No. 3,936,373 shows a device for this purpose. The unit shown is an elongated thimble of generally cylindrical shape peculiarly adapted to be inserted into a standard container, the thimble having the plurality of small openings or perforations in its cylindrical sidewall. The openended top of the thimble is provided with a circumferentially extending outwardly projecting flange configuration for securing the thimble in place in a container. In using the Studer unit and as set forth in Column 5, the user fills the container to approximately one-tenth of its depth with the fecal matter. Then in the laboratory any excess is removed and discarded using a disposable wooden or plastic spatula. An amount of flotation liquid is then added to the receptacle. The receptacle or container is then capped and thoroughly shaken to mix the liquid with the sample feces. The cap is then removed and the thimble is inserted into the top of the transport receptacle. As the thimble gravitationally settles in place under its own weight, the mixture rises in the annular space between the inside of the receptacle and outside of the thimble. When the thimble reaches the bottom of its free fall, the operator presses the thimble to engage the locking flange to the operator. Additional quantities of solution are added to form a slight meniscus. The technician then places a microscope cover glass on the meniscus surface to pick up the surface liquid and the entrained ova. When the test is completed the cap is applied and the container and thimble are discarded.
The Greenwald U.S. Pat. No. 3,819,045 shows a unit for a similar purpose. The device comprises a base having a central shallow well providing a receptacle area for fecal matter, a cylindrical double open ended tube which fits over this base to form a container and a separate perforated piston. A disposable spatula or spoon is used to deposit a quantity of fecal matter in the small well of the base. The cylinder is then assembled to the base around the well and partially filled with a flotation liquid. The mixture is then stirred with a disposable dowel. The piston-like strainer is then manually pressed into the cylinder to force the suspended fecal matter toward the base to a point where the outer end of the piston rod is located below the top edge of the cylinder so that it does not interfere with the meniscus or slide placed over the open top end of the cylinder. A second filling operation then takes place to raise the level of the flotation liquid to the top edge of the cylinder.
The above devices while appearing to be of simplified construction, nevertheless have several obvious disadvantages and drawbacks which the present invention is designed to overcome. For example, in each case, a spatula or spoon is needed to accumulate the fecal matter specimen. This procedure is both time consuming and messy. Furthermore, the spatula is a separate contaminated element which must be discarded before the operator can proceed with the rest of the procedure.
Additionally, in these units, either the thimble or piston have to be further manipulated by the user after flotation liquid has been added. Oftentimes this results in spillage or contact of the operator's hand with the solution. It has also been observed that since neither unit has direct contact agitation or stirring means, maximum separation of ova is not realized, thus contributing to the already unpleasantness of the procedure and increases the possibility of contaminating the operator and laboratory.